Traction battery pack having cell holders with multiple walls

Abstract

A traction battery pack system includes cell holders each having a plurality of walls. The cell holders are disposed along a cell stack axis. Battery cell groups are disposed along the cell stack axis and are each housed in one of the cell holders. The plurality of walls including an axially facing wall disposed between two of the battery cell groups. A tensioning member holds the plurality of cell holders along the cell stack axis.

What is claimed is: 
     
         1 . A traction battery pack system, comprising:
 a plurality of cell holders each having a plurality of walls, the plurality of cell holders disposed along a cell stack axis;   a plurality of battery cell groups disposed along the cell stack axis, each of the battery cell groups in the plurality of battery cell groups housed in one of the cell holders in the plurality of cell holders, the plurality of walls including an axially facing wall disposed between two of the battery cell groups in the plurality of battery cell groups; and   a tensioning member that holds the plurality of cell holders along the cell stack axis.   
     
     
         2 . The traction battery pack system of  claim 1 , wherein each of the plurality of cell holders each include a top wall, a first lateral wall, and an opposite, second lateral wall. 
     
     
         3 . The traction battery pack system of  claim 2 , further comprising a thermal exchange plate, the plurality of cell holders and the plurality of battery cell groups disposed on the thermal exchange plate with the plurality of battery cell groups between the top walls of the plurality of battery cell holders and the thermal exchange plate. 
     
     
         4 . The traction battery pack system of  claim 1 , wherein the plurality of cell holders are polymer-based materials. 
     
     
         5 . The traction battery pack system of  claim 1 , wherein the plurality of cell holders each have four walls. 
     
     
         6 . The traction battery pack system of  claim 1 , wherein the plurality of cell holders are rectangular and have an open wall that faces axially. 
     
     
         7 . The traction battery pack system of  claim 1 , further comprising at least one busbar secured each of the cell holders in the plurality of cell holders. 
     
     
         8 . The traction battery pack system of  claim 1 , wherein the tensioning member is a tensioning rod. 
     
     
         9 . The traction battery pack system of  claim 1 , wherein the tensioning member is a tensioning band. 
     
     
         10 . The traction battery pack system of  claim 1 , wherein each of the battery cell groups in the plurality of battery cell groups contacts two cell holders within the plurality of cell holders. 
     
     
         11 . The traction battery pack system of  claim 10 , wherein each of the battery cell groups in the plurality of battery cell groups contacts axially facing walls of the two cell holders within the plurality of cell holders. 
     
     
         12 . The traction battery pack system of  claim 1 , wherein at least some of the cell holders in the plurality of cell holders are spaced from axially adjacent cell holders along the cell stack axis. 
     
     
         13 . The traction battery pack system of  claim 1 , wherein a distance between axially adjacent cell holders varies along the cell stack axis. 
     
     
         14 . The traction battery pack system of  claim 1 , wherein the plurality of battery cell groups are a plurality of pouch-style battery cell groups. 
     
     
         15 . The traction battery pack system of  claim 1 , wherein the plurality of cell holders and the plurality of battery cell groups are compressed along the cell stack axis. 
     
     
         16 . A traction battery pack system, comprising:
 a plurality of cell holders disposed along a cell stack axis, the plurality of cell holders each having an axially facing wall, a first lateral wall, and a second lateral wall;   at least one busbar associated with each cell holder, the at least one busbar mounted to the first lateral wall, the second lateral wall, or both;   a battery cell group housed within each cell holder and disposed along the cell stack axis, the battery cell group having at least one terminal secured to the at least one busbar; and   a tensioning member that holds the plurality of cell holders along the cell stack axis.   
     
     
         17 . The traction battery pack system of  claim 16 , further comprising a thermal exchange plate, the plurality of cell holders each open to the thermal exchange plate so that the battery cell group can interface directly with the thermal exchange plate. 
     
     
         18 . The traction battery pack system of  claim 17 , wherein the plurality of cell holders each include a top wall, the thermal exchange plate and the top wall on opposite sides of the battery cell group. 
     
     
         19 . The traction battery pack system of  claim 16 , wherein the at least one busbar includes a first busbar mounted to the first lateral wall and a second busbar mounted to the second lateral wall.